franklin



4 Sheets-Sheet 1. B. FRANKLIN 8a D. H. FLETCHER.

M. A. FRANKLIN, Adminstratrix of B. FRANKLlN, Deceased. ELECTRIC CLOCK.

(No Model.)

No. 559,889. Patented May 12.1996.

7f3 @s /d Y A l 3 K Imm (No Model.) 4 Sheets-sheen 2. B. FRANKLIN & D. H. FLETCHER. M. A. FRANKLIN, Administratrix of B. FRANKLIN, Deceased. ELECTRIC CLOCK. No. 559,889. Patented Mey l2, 1896.

www f -ywewf 4 Sheets-Sheet 3..I B. FRANKLIN 8a D. H. FLETCHER.

(N o Model.)

M. A. FRANKLIN. Administratrix of B. FRANKLIN, Deceased. ELECTRIC CLOCK.

No. 559,889. Patented May 12, 1896.

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rNo Model.) sheets-sheet 4. *l

B. FRANKLIN su D. H. FLETCHER. M. A. FRANKLIN, Administranrix of B. FRANKLIN, Deceased. ELECTRIC CLOCK.

A ANDREW'BEMAHAM.PMUTU-UTMDNVASHINUIDNLDA UNTTED STATES PATENT OFFICE.

BENJAMIN FRANKLIN (MARY A. FRANKLIN ADMINISTRA'IRIX OF SAID BENJAMIN FRANKLIN, DECEASED) AND DAVID H. FLETCHER, OF CHICAGO, ILLINOIS, ASSIGNORS OF ONE-HALF TO GEORGE I'I. MER- RIELL ANI) CALVIN R. BEACH, OF SAME PLACE.

ELECTRIC CLOCK.

SEECIFICATION forming part of Letters Patent No. 559,889, dated May 12, 1896. Application filed April 11,1893. Serial No. 469,953. (No model.)

To @ZZ whom, it ntf/,y concern.-

Beit known that we, BENJAMIN FRANKLIN and Dnvrn Il. FLETCHER, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Electric Clocks, of which`the following is a full, clear, and exact description, reference being had to the accompanying drawings, form ing a part of this specification, in which corresponding letters and numerals of reference in the different iigures indicate like parts.

rlhe object of our invention is to provide an electromechanical clock the mechanical elements of which may be so combined and arranged as to be acted upon by electrical means at stated times, but in such a manner as to utilize but a minimum of battery force. IVe accomplish said result in substantially the following manner: Loosely mounted upon one of the elock-arbors, preferably that next to the escapement-arbor, are two pinions connected to the arbor by means of ratchet mechanism. Racks attached to a pivoted lever are adapted to engage said pinions, said racks being arranged upon opposite sides of said arbor, so that the vibration of the lever may serve to rotate said pinions in one direction, while the reversal of said lever serves to reverse the direction of movement of the pinions. The ratchet mechanism upon said pinions being the same, it follows that the pinions are alternately idle. The result of this action is to cause the arbor to be continuously driven in the same direction as long as the racks are vibratcd. Pivoted to the drivinglever is a shifting-yoke attached to a spring under tension, said yoke being so arranged as to oscillate into one or another of two extreme positions, in either of which it tends to actuatc the lever a proportionate distance. An electric circuit making and breaking device is attached to and caused to vibrate with said lever and to alternatelybring an electromagnet into circuit with a source of electricity as it reaches the opposite extreme positions of its movement. rlhc action of the armature serves to shift the yoke, and thus to continually vibrate the lever having thereon the segmental racks at a uniform rate of speed,

which serves to drive the clock in a given direction. As an open-circuit battery is employed and the electric contact is instantaneous and only occurs at stated intervals, preferably severa-l minutes apart, the extent to which the battery is brought into circuit is very limited, and hence a battery of moderate strength may be used for a long time without requiring replenishment, all of which is hereinafter more particularly described and claimed.

In the drawings, Figure l is a front elevation of the works of ourimproved clock, showing the lever-arm in one extreme position. Fig. 2 is a like viewin which the front plate, pendulum, and certain gears are removed to more clearly show the novel features and in which also the vibratory lever-arm is shown in an opposite extreme position from that shown in Fig. l. Fig. 3 is a like view to that shown in Fig. 2, except that all the gearwheels are removed except those which engage directly with the segmental rack. Fig. 4L is a central vertical sectional view. Fig. 5 is an enlarged front View of the main drivingwheel, showing means for temporarily continuing its movement, said view being taken upon the sectional line 5, Fig. 4. Fig. G is a like view of the reverse or rear side of said wheel, taken upon the line 6, Fig. et. Fig. 7 is an enlarged detail view of one of the driving-pinions and a disk for preventing the backward movement thereof, said view being taken upon the line 7, Fig. 4E. Fig. S is a sectional view in detail taken upon the line 8, Fig. 3, showing our improved circuit maker and breaker.

In the drawings, a represents the frame of our improved clock, in which is mounted in any improved way the usual eseapement-arbor b, a secondary arbor c, which we term the driving-arbor,77 and the minute-hand arbor d. A gear-wheel c, meshinginto apinion upon the escapement -arbor, serves to transmit power to the latter, and thereby to aetuate the pendulum, while a pinion f, Fig. 4, upon said driving arbor serves in turn to transmit power to the train of gears which drive the hands.

Loosely mounted upon the driving-arbor c are two pinions g and 71., which are intended to cause the rotation of said arbor in the manner hereinafter set forth. To the loose pinion gis, by preference, rigidly attached a disk t', Figs. 4- and 6, which is adapted to be engaged by a spring-actuated pawlj, Fig. G, pivotally attached to a disk 7c, which is rigidly secured to said arbor. The gear-wheel c, which, as stated, engages with a pinion upon the escapementarbor, is loosely mounted upon the driving-arbor c and connected with the disk 7U' by means of a spring l, as shown in Figs. 5 and 6. Vhen the disk 7c is propelled in the direction indicated by the arrow in Fig. G, the pawlj is brought into engagement with the disk i', the spring' Z is placed under tension, and the gear cis thereby caused to rotate an instant after the pinion g has been caused to move, the object of which will be hereinafter explained.

Rigidly attached to the pinion 7L is a disk on, Figs. 3, 4, and 7, which is adjacent to a larger disk n, which is rigidly secured to the arbor c. A spring-actuated pawl o is loosely mounted upon the disk n and caused to bear against the disk m in the manner shown. It will be observed that the positions of the pawls j and o are the same with reference to the direction of movement of the arbor c, so that while the pinion g, for exam ple, is rotated in the direction indicated by the arrow in Fig. G the disk t' is also rotated in the same direction, thereby rendering the pinion g for the time being a driver, while the pinion 7L is idle; but when the latter is driven in the direction shown by the arrow in Fig. 3 then the disk 'a is caused to rotate through the engagement of the pawl o. A pawl j), Figs. 3 and 7, is pivotally attached to the frame and adapted to engage by means, preferably, of its own gravity with the disk n to prevent the backward movementI of the latter, which is intended to rotate at all times in a given direction, as indicated by the arrow. Said disk is preferably provided with very fine ratchetteeth, or what is more commonly termed a milled7 periphery, in order to prevent the pawl from slipping. The manner of accomplishing this continuous movement by means of segmental racks will now be explained.

Pivoted at q, at or near the bottom of the frame, (see Figs. l to 4, inclusivc,) is a shaft r, Figs. 4f and ll, to which is rigidly secured a lever s, which is extended upwardly therefrom and provided at and near its upper end with segmental gears t n, which are arranged in parallel vertical planes, so that the one may engage with the pinion g, while the other engages with the pinion 71,. As the gear t is placed above the pinion g, while the gear u is placed below the pinion 7L, it follows that the vibration of the levers, which is accomplished in the manner hereinafter set forth, serves to rotate said pinions in opposite directions, and as each pinion is alternately an idler, owing to the direction of movement of the lever, it follows that in whatsoever direction the lever is caused to vibrate the direction of movement of the arbor c remains constant, as hereinbefore stated. lt is obvious that the same result maybe accomplished by placing both of the segmental gears or racks t u either above or below said pinions and .reversing the pawlsj o.

The direct mechanical means for causing` the vibration of the lever s is as follows: EX- tending upwardly from the pivotal shaft 0 is an open framework fr, to the top of which, at e', is pivoted a depending lever-arm e2, to the lower end of which is attached a wire or cord 1U, which is in turn attached, preferably by means of an adjustable screw w', to a spring fr, arranged by preference at or near the top of the framework. Springs t3 fr, attached to the frame fr, are intended to serve as elastic stops for the lower end of the lever-arm ft2 as it is shifted from one to the other of two extreme positions in the mannerhereinafter set forth. As thc spring x is always under tension, it tends through the lever-arm ft2 to cause the lever S to vibrate in one or another direction according to the position of said lever-arm. In Fig. l., for example, the leverarm is shown as being tilted to the right, and hence the line of draft of the wire w is at the right of the pivotal point q of said lever, and it is obvious, therefore, that the latter would be caused to move in the direction indicated by the arrow in Fig. l. On the other hand, when the lever-arm 'n2 is in the position shown in Figs. 2 and 3 the line of draft of the wire fw is upon the left of the pivotal point (j, and hence the levers is actuated toward the right. In Figs. l and 2 the lever .s is shown as being in the same position, although the lever-arm e2 and wire w are in opposite positions. This is accounted for from the fact that while the lever-arm s moves at a slow and regular speed the lever-arm frz is shifted instantly. In Fig. l the lever s is shown as being substantially in its extreme left-hand position at the instant before the lever-arm fr2 is shifted, while in Fig. 2 the lever s is represented as being in the same position, but at the instant when the lever-arm r2 is shifted to an. opposite position. These same conditions are true in connection with the lever when it reaches its extreme right-hand position.

As there is a tendency on the part of the lever-arm e2 to rebound when shifted, we attach to the frame a spring q', which adapted to engage with the lower end of said leverarm and hold it temporarily, as shown in. Fig. 2; but as the lever s is moved the end of the lever-arm is drawn away from contact with the spring q', as shown in Fig. Il, thus leaving the lever-arm free to be tilted at the proper time, when it will again be temporarily locked in an opposite position by the proj ection upon said spring, as shown in dotted lines. ln order to understand this action, it should be borne in mind that the spring' q/ is limited in its upward movement by the shaft IOO IIO

q, which forms a stop therefor; but as the lever s is moved, for example, to the right, as shown in Fig. 3, and as the lever-arm @2 is mounted upon the lever s, and hence partakes of the movement of the latter, it follows that the lower end of the lever-arm 'U2 is caused to travel in the arc of a circle, the radius of which is equal to its distance laterally from the pivotal point of the lever s. This is illustrated in Figs. 2 and 3. In the former, the lever s being in its extreme lefthand position, the lever-arm c2 is shown as being in engagement with and locked by the spring, which has yielded to permit the lower end of the lever-arm to slip past its end; but in Fig. 3 the lever s is in its eXtreme righthand position, which movement has served to lift the lever-arm above the end of the spring, which is prevented, as described, from rising.

From the foregoing it is clear that said clock may be propelled mechanically bythe action of the spring c alone during the vibration of said lever s in either direction, and it is only to shift the lever-arm from one extreme position to the other at the proper time that electricity is brought into action at all. As the shifting of the lever-arm is intended to be made at regular intervals and the electric circuit closed through the vibratory action of the lever s itself when it reaches a given point in its travel in either direction it follows that no stop is required to limit the movement of said lever in either direction.

The electric circuit may be traced as follows: from the battery s" over the wire 13 to the insulated bracket 1, thence through the lever-arm 2 to the contact-point 11 when brought into contact therewith, as hereinafter stated, thence along the spring 10 to the wire 14, thence through the coil of the electromagnet .2', and thence by the line 12 to the opposite pole of the battery, thereby completing the circuit. The electrical appliances for shifting said lever-arm and for making and breaking the electric circuit, so as to cause the continuous and regular vibration of the lever s, are as follows: Rigidly attached to the lever-arm is a cross-bar fu, upon which loosely rests a friction-roller y upon the end of a lever-arm y, which is pivoted at y/2 to the framed. An armature yiis attached to said lever y, which armature is in operative proximity to the poles of an electrom agnet s, supported upon thc frame and electrically connected with a suitable battery e", Figs. 1 and S).

Pivoted upon a bracket 1, Figs. 1, 2, 3, and S, which is properly insulated from the frame c, is an elbow-lever 2, which is normally held in a given position against a stop 3, Figs. l, 2, and 3, by means of a spring 4. The lower end of said lever is provided with a notch 5, which, when said lever is in a normal position, is adapted to receive therein, as indicated in Figs. 1, 3, and 8, a V-shaped metal plate 6, which is rigidly attached to a bracket 7, secured in turn to the frame a, as shown in said last-named figure. Said` plate 6 is provided with an opening 9 therein for the purpose hereinafter stated. The plate 6 and lever 2 are so adjusted with reference to each other that they do not at any time come into contact, the plate being intended to form a guide to control the movement of a contactspring 10, one end of which is attached to the lever s, as shown. The free end 1l of said spring is reduced in size, so as to readily pass through the opening 9 when brought opposite thereto. The spring 10 is preferably weak and of such a length that the part 11 may be brought into contact with the lever 2 when the latter is in its normal position, s0 as to close an electric circuit. Said spring 10 is electrically connected with one pole of an electric battery e', as well as with the electromagnet z, while the opposite pole of said battery is electrically connected with the lever 2, as clearly shown in Fig. 1, by means of the lines 12 and 13, respectively. As the lever S is vibrated the spring 10 is in turn vibrated so as to cause the part 11 to pass above or below the upper or lower edge, as the case may be, of the plate 6, and as the tendency of said spring is to move in a given plane, except when deflected by the oblique wings or flanges of the plate 6, it follows that when it slips off from the edge of said plate its lateral movement causes it to be brought into contact with the lever 2, as indicated in Figs. 1 and 8, the dotted lines in said latter figure indicating the path of movement -of said spring. As soon as said contact is madethe electric circuit is completed, and the magnet e' being excited the armature ys is attracted, thereby causing the end of the lever y to actuate the cross-bar e5, and thus tilt the lever-arm r2, by which action also the upper end of the lever 2 is depressed against the action of the spring 4, thus withdrawing the lower end of said lever away from contact with the spring 10, as shown in Fig. 2, which instantly breaks the electric circuit and permits the lever 2 to resume its normal position. This making and breaking of the circuit occurs with each vibration of the lever .5'.

Having thus described in detail the various features of our improved clock, we will now describe its operation. Assuming the electric circuit to have been closed in the manner described, the lever-arm v2, through the action of the lever y, is tilted to the left, as shown in Fig. 2. The upper end 0f said lever s is at this time in its extreme left-hand position, and as the line of draft from the drivingspring x is, by the tilting of said lever-arm, changed from the right to the left hand side of the pivot q the movement of the lever s is thereby reversed, which causes the work of driving the arbor c to be shifted from one to the other of the pinions g 7L, thus causing said arbor, as stated, to be rotated continuously in the same direction. The pressure upon the gear-wheel E is maintained through the IOO IIO

action of the spring Z during the momentary stop caused by the shifting of the lever-arm. This prevents any loss of time which might otherwise be occasioned from varying the pressure upon the eseapement-wheel. The knife-edged pawl p prevents any back action of the disk n, and hence the spring L is kept under tension at all times during the movement of the lever s. The lever s having reached its full limit of .movement to the right, as shown in Fig. 3, the spring lO is again brought into contact with the lever 2, as shown, when, as a result, the lever-arm t2 is, through the action of the electromagnet, tilted to the right, which causes the movement of the lever s to be again reversed. It will thus be seen that the clock is driven directly by the action ot the spring which is always under tension, and that the electric action is only employed to shift the lever-arm It is obvious that the time required for the lever s to vibrate may be varied indefinitely; but as it requires, in the construction shown, about five minutes for it to complete a movement in a given direction, and as the electric circuit is closed only for an instant at the end of that movement, it follows that the work required of the battery may be reduced to a minimum, and hence that it may last indeiinitely. A further advantage is that the :trietion incident to the use ol' a long train of gears is largely dispensed with, in that the power is applied to the arbor next to the escapement-arbor.

Having thus described our invention, we claiml. The combination with a clock-train, of a pivoted lever in operative connection with the driving-arbor ol' the train, means for actuating said lever, a shifting device for alternately changing the direction of its movement, an armature in operative connection with said shiftin g device, a source of electricity, and means for automatically making and breaking the electric circuit at regular intervals corresponding to the movement ot said driving-lever, substantially as described.

2. The combination with a clock-train, of a driving-arbor, a segmental rack for actuating said driving-arbor and an electrical shifting device for automatically reversing the direction of movement of said rack at predetermined intervals, substantially as described.

f3. The combination with a clock-train, ot a drivin g-arbor interposed between and in direct connection with the hand and escapement arbors respectively, a pivoted lever having segmental racks for actuating said driving-arbor, means for applying driving power thereto, and an electrical shifting device forautomatically reversing the direction of movement of said driving mechanism at regular intervals, substantially as set forth.

at. In an electric clock, the combination with a driving-arbor, of independent pinions connected therewith by means of ratchets, a vibratory lever having segmental racks arranged to engage with said pinions respectively, a shifting lever-arm in operative connection with said lever, a driving-sprin g connected with said yoke, the line ot draft from which may be alternately shifted from one to the other side of the pivotal'point of said vibratory lever as the latter is shifted, and means for shifting said lever-arm, substantially as described.

5. The combination in an electric clock, of a vibratory lever provided with segmental gears, independent pinions loosely mounted upon a driving-arbor and in operative engagement with said segmental gears, ratchets tor connecting said pinions with said arbor, a shifting lever-arm pivoted upon said vibratory lever, a spring in operative connection therewith for actuating said lever, an electromagnet, a source of electricity, an armature in operative connection with said magnet and with said shifting lever-arm, and means for making and breaking the electric circuit with each vibration ot said vibratory lever, substantially as shown and described.

G. The combination of a driving-arbor, suitable gears mounted thereon, a vibratory lever having segmental gears in operative connection with said arbor-gears, a spring for actuating said vibratory lever, means for alternately shifting the point of draft upon said lever from one to the other side of its pivotal point, a source of electricity, an electromagnet, an armature, a lever in operative connection therewith and with said shifting device, and a circuit maker and breaker for making and breaking said electric circuit with each vibration et' said lever, substantially as shown and described.

7. rlhe combination with the driving-arbor c, of the loose pinions g h, disks n 7a, rigidly attached to said arbor and connected with said pinions by means of suitable pawls, segmental racks in operative connection with said pinions, and means for moving said racks back and forth at regular intervals, whereby said arbor may be driven continuously in one direction, substantially as set forth.

S. The combination in a clock-movement, of a vibratory driving-lever having segmental racks for actuating the drivin g-arbor, a shitting pivoted lever-arm for changing the direction of movement of said lever, a drivingspring in operative connection with said yoke, an electromagnet having its armature in operative connection with said yoke, a source of electricity, a normally open circuit and a vibratory circuit maker and breaker in operative connection with said shifting lever, whereby the circuit may bc made and broken and the lever-arm shifted with cach vibration of said drivin g-lcver, substantially as shown and described.

The combination with the vibratory lever s, of the shifting lever-arm r2, a drivingspring in operative connection therewith, an d means for shifting said lever-arm at regular intervals, substantially as described.

IOO

IIO

l0. The combination of a vibratory drivinglever, a shifting lever-arm, a driving-spring, an armature, an electromagnet, a source of electricity, a lever for connecting` said armature with said lever-arm, lever 2, contactspring 10, plate 6, and suitable electrical connections, substantially as shown and described.

1l. The combination with the vibratory lever s and electrical means for alternately shifting the movement thereof, of the circuit making and breaking device consisting` of the lever 2, plate G, contact-spring l0, a source of electricity, and suitable electrical connections, substantially as shown and described.

12. The combination of a vibratory lever, a shifting device for automatically shifting` the direction of movement of said lever, and a locking` device for temporarily and automatically locking said shifting,` device when iirst shifted, substantially as set forth.

In testimony whereof We have signed this speciiication, in the presence of tWo subscribin g Witnesses, this 28th day of February, A. D.

BENJAMIN FRANKLIN. DAVID I-I. FLETCHER. Vitiiesses:

W'. H. OHAMBERLIN, FLORENCE KING. 

